Week 5 Unit Tests

Testing my twittr

题目描述：

测试Problem Set2中Setting up my twttr程序；

题解：

twttr.py

def main():
    print("Output: ", shorten(input("Input: ")))



def shorten(word):
    ans = ""
    for i in word:
        if i.lower() not in ['a', 'e', 'i', 'o', 'u']:
            ans+=i
    return ans

if __name__ == "__main__":
    main()

test_twttr.py

from twttr import shorten

def test_shorten():
    assert shorten("aeiou") == ""
    assert shorten("AEIOU") == ""
    assert shorten("Twitter") == "Twttr"
    assert shorten("What's your name?") == "Wht's yr nm?"
    assert shorten("CS50") == "CS50"

Back to the Bank

题解：

bank.py

def main():
    str = value(input("Greeting: "))
    print(f"${str}")

def value(greeting):
    greeting = greeting.strip().lower()
    if greeting.startswith("hello"):
        return 0
    elif greeting.startswith("h"):
        return 20
    else:
        return 100

if __name__ == "__main__":
    main()

test_bank.py

from bank import value

def test_bank():
    assert value("Hello") == 0
    assert value("Hello, Newman") == 0
    assert value("How you doing?") == 20
    assert value("What's happening?") == 100

Re-requesting a Vanity Plate

题解：

plates.py

def main():
    plate = input("Plate: ")
    if is_valid(plate):
        print("Valid")
    else:
        print("Invalid")


def is_valid(s):
    if len(s) < 2 or len(s) > 6:
        return False
    if not s[0].isalpha() or not s[1].isalpha():
        return False
    if not all(ch.isalnum() for ch in s):
        return False

    flag = False
    for ch in s:
        if ch.isdigit():
            flag = True
        if ch.isalpha() and flag:
            return False

    for ch in s:
        if ch.isdigit():
            return ch != "0"

    return True


if __name__ == "__main__":
    main()

test_plates.py

from plates import is_valid

def test_plates():
    assert is_valid("CS50") == True
    assert is_valid("CS05") == False
    assert is_valid("CS50P") == False
    assert is_valid("PI3.14") == False
    assert is_valid("H") == False
    assert is_valid("123456") == False
    assert is_valid("OUTATIME") == False

Refueling

题解：

fuel.py

def main():
    print(gauge(convert(input("Fraction: "))))


def convert(fraction):
    while True:
        try:
            x, y = map(int, fraction.split("/"))
            if y == 0:
                raise ZeroDivisionError
            if x > y:
                raise ValueError
            return round(x / y * 100)
        except (ValueError, ZeroDivisionError):
            pass


def gauge(percentage):
    if percentage <= 1:
        return "E"
    elif percentage >= 99:
        return "F"
    else:
        return f"{percentage}%"


if __name__ == "__main__":
    main()

test_fuel.py

from fuel import convert, gauge
import pytest


def test_convert():
    assert convert("3/4") == 75
    assert convert("0/100") == 0
    assert convert("100/100") == 100
    assert convert("99/100") == 99

    with pytest.raises(ValueError):
        convert("x/y")

    with pytest.raises(ZeroDivisionError):
        convert("1/0")


def test_gauge():
    assert gauge(0) == "E"
    assert gauge(1) == "E"
    assert gauge(100) == "F"
    assert gauge(99) == "F"
    assert gauge(2) == "2%"

Week6 File I/O

Lines of Code

题目描述：

计算.py文件代码有多少行；

题解：

import sys

## 判断输入是否合法
if len(sys.argv) != 2 or not sys.argv[1].endswith(".py"):
    sys.exit("Invalid arguments.")

## 读取文件
try:
    with open(sys.argv[1]) as file:
        sum = 0

        ## 排除注释
        for line in file:
            if line.strip() and not line.lstrip().startswith("#"):
                sum += 1

        ## 输出结果
        print(sum)
except FileNotFoundError:
    sys.exit("File does not exist.")

Pizza Py

题解：

from tabulate import tabulate
import csv
import sys

## 判断输出是否合法
if len(sys.argv) != 2 or not sys.argv[1].endswith(".csv"):
    sys.exit("Invalid arguments.")

## Note that the tabulate package comes with just one function, per pypi.org/project/tabulate. You can install the package with:
## pip install tabulate

try:
    with open(sys.argv[1]) as file:
        print(tabulate(csv.DictReader(file), headers="keys", tablefmt="grid"))
except FileNotFoundError:
    sys.exit("File does not exist.")

Scourgify

题目描述：

题解：

import csv
import sys

## 判断输出合法性
if len(sys.argv) != 3 or not sys.argv[1].endswith(".csv"):
    sys.exit("Invalid arguments.")

try:
    with open(sys.argv[1]) as input, open(sys.argv[2], "w", newline="") as output:
        reader = csv.DictReader(input)
        writer = csv.DictWriter(output, fieldnames=["first", "last", "house"])
        writer.writeheader()
        
        for row in reader:
            last_name, first_name = row["name"].strip().split(", ")
            writer.writerow(
                {"first": first_name, "last": last_name, "house": row["house"]}
            )

except FileNotFoundError:
    sys.exit("File does not exist.")

CS50 P-Shirt

题解：

from PIL import Image, ImageOps
import sys

if len(sys.argv) != 3:
    sys.exit("Invalid arguments.")

input = sys.argv[1]
output = sys.argv[2]
types = (".jpg", ".jpeg", ".png")
if (
    not input.endswith(types)
    or not output.endswith(types)
    or input.split(".")[1] != output.split(".")[1]
):
    sys.exit("Invalid arguments.")


shirt = Image.open("shirt.png")
try:
    with Image.open(input) as im:
        im = ImageOps.fit(im, shirt.size)
        im.paste(shirt, shirt)
        im.save(output)
except FileNotFoundError:
    sys.exit("File does not exist.")